Quadrupolar binary fluid mixtures critical lines from a hard-sphere Lennard-Jones quadrupolar molecular model

Abstract

The critical behavior of binary mixtures of fluids with permanent quadrupole moments is investigated by the application of the thermodynamic perturbation theory. Here the pair potential function is represented as a hard-sphere reference system being perturbed by the Lennard-Jones potential plus a quadrupole–quadrupole interaction. Good agreement with experimental critical loci is found for N2–H2, N2–He, CO2–C2H6, and CO2–C2H4 binary mixtures.